It's true. Back when Tevez was young and he was winning Libertardores every year his reputation was almost as strong as Ronaldo today. He was a leader, he led his club to victory. People back then were drooling at the idea of him coming to Europe. Which he eventually did, and it was... West Ham. Ever since that disappointment he's never come anywhere near reclaiming that once strong reputation. And the latest is a 12m sale, ie. sold for scrap.
Btw same thing is true for Diego and Robinho. Though Tevez was more hyped than they were afaik.